A steer by wire system is a steering system separating a mechanical connection between a steering wheel and a driving wheel of a vehicle and may steer the vehicle by receiving a rotation signal of the steering wheel through an electronic control unit (ECU) and operating a steering motor connected to the driving wheel on the basis of the received rotation signal.
The steer by wire system removes the mechanical connection structure of the existing steering system, and thus has advantages of increasing layout freedom due to the configuration of the steering system, improving fuel efficiency, and removing disturbance reversely input from a wheel.
However, the steer by wire system has a disadvantage in that a driver may not properly fed back with steering information that the driver requires, due to the disconnection of the mechanical connection structure.
For example, the existing steering system need not separately generate a steering wheel reaction torque due to the mechanical connection structure by a universal joint, or the like, but the steer by wire system does not have the mechanical connection structure and therefore needs to generate the steering wheel reaction torque or a recovering wheel reaction torque using a motor, or the like.
Further, even if a tire reaches a rotation limit and thus no longer returns, the steering wheel may be continuously rotated, and therefore a rotation range of the steering wheel needs to be limited.
Therefore, in the steer by wire system field, a technology of constantly limiting a rotation angle of the steering wheel is required and a mechanism of mechanically limiting the rotation range of the steering wheel has been variously proposed in recent years.
However, the mechanism of mechanically limiting a rotation and the mechanism of generating a steering wheel reaction torque are separately installed to reduce unique space efficiency of the steer by wire system.
The contents described as the related art have been provided only for assisting in the understanding for the background of the present invention and should not be considered as corresponding to the related art known to those skilled in the art.